This invention relates to a pontoon assembly for watercraft which comprises a series of modular pontoon assemblies (modules) which may be linked together to form an integrated pontoon. The modular components are similarly shaped (with the exception of the bow and stem modules) and each module is provided with a mating face surface profile which ensures that two adjacent modules may be easily assembled together in an interlocked relationship at the mating faces. When a series of such modules are assembled together with the mating faces interlocked together, the result is complete pontoon having all the floatation advantages associated with the prior art single unit pontoon assembly in common use today but in addition allows for fast and speedy replacement of any part of the pontoon assembly which might be damaged during use. It is not necessary to remove the entire pontoon assembly to replace one of the modular components.
Each module of this invention is preferably formed from a tough plastic material which is capable of undergoing substantial distortion without experiencing rupture. Such modules may be successfully formed through blow molding or by a centrifugal casting process. The result is a tough durable lightweight module which when assembled together with a series of like modules may ultimately be formed into an integral pontoon which is capable of replacing the standard metallic pontoons used on watercraft etc. The resulting pontoon composed of a plurality of interlocking modules is available at a fraction of the price of the elongated metallic cylindraceous pontoons of the prior art. Individual modules in the completed pontoon may be easily removed and replaced without the requirement of complete removal of the entire pontoon from the watercraft. The prior art pontoons either require complete removal of the pontoon or the raising of the watercraft with sophisticated lifting equipment to enable a repair to the pontoon whilst it is still attached to the watercraft.
Pontoons have been used to supply floatation for houseboats, barges, docks, rafts, bridges, etc. for years. Prior art pontoons have usually taken the shape of an elongated, hollow metal cylinder and in instances where the pontoons are used as floatation devices for moving watercraft, etc. the leading and trailing portions of the pontoon are usually shaped to minimize the resistance to motion of the pontoon through the water.
Recently pontoons have been developed which are more of a modular nature and which have been used for docks, rafts and other stationary floating objects so that the floatation may be adjusted by adding more units to the floating raft or dock assembly. The versatility of the modular concept for floatation devices has led to wide acceptance of hollow plastic pontoon modules for docks and rafts etc.
Pontoons for houseboats and other moving watercraft have generally been fabricated from sheet metal stock to form a hollow, cylindrical, metallic vessel on which a superstructure is mounted.
Over the years, pontoon equipped houseboats have suffered from one serious deficiency. If the metallic pontoon suffered puncture damage anywhere along its length it is necessary to raise the pontoon out of the water in order to be able to carry out a repair. This necessitated that the houseboat be tipped in some fashion or other or that the entire craft be lifted out of the water to effect a successful repair. At times it will be found that if the damage to the pontoon is severe enough, the entire pontoon must be removed from the watercraft to effect a satisfactory repair.
It is well recognized that a large industry has evolved in which pontoon equipped houseboats are rented to vacationing persons who have had little or no experience in operating watercraft of this type and size. As a result, it is not unusual for a novice to damage the pontoons on such rented watercraft. Repairing damaged pontoons can be prohibitively expensive.
The modular pontoon assemblies of this invention may be ideally applied to applications such as houseboats and other types of watercraft such as barges, sightseeing craft, etc. which are not primarily intended for operation at high speeds, but where damage to the pontoon assemblies is an occupational hazard. The modular pontoon assembly of this invention is formed of a series of identically shaped hollow molded plastic modules which are quite resilient and which have the ability to distort upon impact without suffering puncturing damage. The material is resistant to tearing etc. when subjected to unintentional scraping or abrasive scrubbing on the pontoon surface.
The pontoons themselves are formed into a predetermined shape so as to keep the resistance low when the watercraft is in motion, and the sides of the pontoon are shaped to add increased resistance to impact damage during docking and mooring.
Each pontoon is provided with a pair of spaced apart upright parallel flanges at the upper surface thereof in which a series of spaced transverse bolt holes are formed. A pair of substantially xe2x80x9cCxe2x80x9d shaped pontoon rails are supplied on the mounting craft to engage the flanges on their outside surfaces for mounting the pontoons on a watercraft. The flanges of the pontoons are formed to be spaced apart sufficiently to thus fit between the xe2x80x9cCxe2x80x9d shaped pontoon rails. There is just sufficient clearance between the rails and flanges to allow the flanges formed on the top of each pontoon module to slide between the pontoon rails. When a pontoon is located in the desired position and location between the pontoon rails, one or more through bolts are passed through the matching holes in the rails and the upright flanges on the top of the pontoon module to fix the pontoon to the watercraft.
The complete pontoon for a watercraft may comprise several modules serially mounted on the pontoon rails to provide the desired floatation. The modules at each end of the pontoon assembly preferably have a curved water engaging surface (similar to a ski) to cut down losses when the craft is moving. The mounted modules are preferably maintained in a state of compression in the string. They are pressed together by a jacking means or a winch to ensure a tight fit between adjacent modules forming the complete pontoon. The through bolts passing through the pontoon rails may be tightened to secure each module in its xe2x80x9chomexe2x80x9d position on the pontoon rails after the modules have been pressed together.
U.S. Pat. No. 5,355,825 Oct. 18, 1994
This patent is directed to an aquatic float the primary purpose of which is to supply floatation for aquatic structures such as docks, rafts or platform boats etc. The float is of a modular type having a pair of upright longitudinal flanges formed in the top surface thereof embrace xe2x80x9cstandard dimensional lumberxe2x80x9d. The longitudinal flanges are provided with moulded in place fastener receivers.
U.S. Pat. No. 4,768,456 Sep. 6, 1988
This patent describes a modular float system which is ideally suited for docks and rafts. The patent describes a floating platform, the buoyancy of which is provided by large hollow plastic floats, which are serially held in place by a raft assembly which is mated into grooves formed in the top of each module. In this instance, the mating plastic grooves are provided with ridges to tightly engage the mating members of the raft assembly.
Each module is provided with an interlocking surface of mating with the adjacent module so that the integrity of the float assembly is maintained.
This assembly which is directed to floating docks and rafts might be adaptable for use as a pontoon assembly for a houseboat etc. but the construction of the interlocking raft and float surfaces is such that each module tends to be xe2x80x9clockedxe2x80x9d in place one the raft members have been properly seated in the provided recesses in the top of the float surface. It would almost require a jacking device to separate a float module from the raft. The interlocking assembly (dove tail) shown in FIGS. 5 and 6 may yield further problems for separation of adjourning floats if one float must be removed from the system
U.S. Pat. No. 5,947,049 Sep. 7, 1999
This invention relates to a boat lift or a walkway which comprises a set of hollow plastic modules which are mounted on a pair of rails by means of through bolts. Because of the configuration of the device of this invention, it is not applicable to the pontoon assembly of this invention.
U.S. Pat. Re No. 24837 Jun. 4, 1960
U.S. Pat. No. 2,879,735 May 31, 1959
U.S. Pat. No. 3,448,709 Jun. 10, 1969